1 A student collects several plants and pebbles from a riverbank, places them in an aquarium,
and records observations for 15 days. The sizes of the plants increase, while the sizes of the
pebbles remain the same. The student classifies the pebbles as nonliving things.
Which criteria does the student use as the basis for the classification?
A ability to grow
B ability to move
C ability to reproduce
D ability to respond to stimuli

How does natural selection change thephenotypes within a population over time?

At which point is crust neither created nor destroyed? island chain mid-ocean ridge divergent boundary transform boundary

Even though the ostrich is a flightless bird, ostriches still possess wings that stretch approximately two meters across when fully extended. scientists speculate that when dinosaurs became extinct, some of the birds that lived during that time became land dwellers since they were able to consume the food that the dinosaurs once ate. over time, these species grew larger and heavier. eventually, the ostrich species became too big to fly. the wings found on ostriches are known as a. analogous structures. b. homologous structures. c. vestigial structures. d. symmetrical structures.